Cypripedium seedlings

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Well-Known Member
Mar 26, 2018
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Cape Girardeau, Missouri
First post minus initial greeting so I apologize if it’s a little long and I ramble a bit.

I have 6 seedlings a piece of Kentuckiense and Pubescens coming in a few weeks from Spangle Creek labs. I plan to grow 3 seedlings of each indoors under lights and the other 3 outside in pots in the ground. Good/bad idea? Thought it would increase my chances of survival.

Indoors I grow in the basement on a 3 teer shelf that is 18” by 36” and have 1 cheap LED shop light on top and an old T8 shop light on 2nd shelf, 3rd shelf was supplies. I was going to put the cypripedium seedlings there and buy more lights or convert old T8s to direct LED with Sunritek? But after reading naoki posts on lighting I’ve realized I’m wayyy under my needed FC/Lux based on light meter app that I download on my phone which is reading around 350lux with the LED and 450 with the T8. And I thought the LED was brighter. Don’t have a PAR reader. I have no grow tent/mister/fan. 1st and 2nd shelf is full of an assortment of tropical orchids and a few African violets. Sounds like I need to upgrade some things? So on Sunritek website you can get 2 “samples” free (will order more) but what is the CRI and PF option I should choose? And I want UL certified correct? Or what Sunritek options would be best for Cypripedium?

Outside, I could pot out and bury the pots and could put them under tall canopy shade. Most of my property is mature oak/hickory with some mature ash(alive for now). I’m on top of the hill and don’t have a protected valley nor east face exposure that doesn’t get nearly full sun most of the day.

On media, I may have over purchased. OK, I know I did. Spangle Creek labs suggest Turface MVP/perlite mix and Metro-mix 560/perlite or sand mix. I purchased a 50lbs bag of Turface MVP for $10 and a 2klg bag of 560 from the university I will add perlite/sand to them as suggested. But at what ratio? I’ve read tons of different mixes for these two cypripedium but what is best for my climate? Trial and error for sure, but any suggestions? I’m on the boarder for 6b and 7a in Cape Giraradeau, MO just north of the delta region. It can be -5F to over 100F in summer. Rain? dought/flood you name it over the last few years.

Sorry for the long post I tried to cover everything I could think of. I appreciate your thoughts and suggest in this new undertaking.

I haven't had too much long-term success with Cyps. I had C. guttatum from Spangle Creek, but I could keep it only 3 years or so. If you haven't grown Cyps before, bigger plants would be easier.

You might want to ask Sunritek if the free samples include the shipping cost. I'm guessing not. Since shipping is expensive, it isn't worth if you aren't going to get a lot (e.g. 20 bulbs). But to answer your question, CRI doesn't matter too much (I would go for the lowest CRI). Is PF, a power factor? Higher PF is better, but in terms of money, it doesn't matter. I guess if there is an option of UL certified or not, it would be better to have it (if it doesn't cost extra).

Also, isn't electricity in Mo super cheap (like <10cents/kWh)? If so, it will take a long time to recover the cost you pay for higher efficiency.

Are you sure about the unit of your measurement. At 12", a shoplight with 2x T8 fluorescent bulbs should give about 300-350fc (not lux).
I must have been reading the app backwards. You are correct i’m getting about 450fc off a single T8 40w bulb. And 350 with the LED. I’m at about 8 cents a kWh, so I see what your saying. Where is the costs savings with the extra costs of the LED. I’ll just find something cheap at one of the local home supply stores. I assume PF is power factor. Sunritek doesn’t elaborate on it in the sample order.

Thanks for your input Naoki
Recently found a cheap LED shop light to increase the amount of light my current set up and seedling cyps will get. I found a 42W, 5000k, 4,200 lumen LED shop light for $25. Would this be to much light at 12” above my plants? Or should I have even have 2 sets of shop lights? I can increase the distance if needed, I don’t want to burn the leaves. Just thought this was a cheap price for the specs.

Link to LED below.
It probably works well. I'm guessing that you'll get 300-500fc at 12". It seems to be reasonable for seedlings just out of flask, but I'm not completely sure about the good amount of light for the two species. Since they are not tall out of flask (around 1-2"), you can bring the plants closer to the light by putting something under the pots.
I was just thinking just one. I don't have any experience with this particular one, so I'm just guessing that one shoplight is similar to 1x T5HO or 2x T8. If you need to cover a wider area, you probably want to have 2. When I use shoplight fixtures converted with Sunritek, I use 2 strips (4 bulbs) per 48"x18" shelf. Sunritek 12W is 1800lm and 15W is 2100lm. The beam pattern influences the intensity, but Table 1 of will give the approximate intensity.
Jason, I can't help you with your light set-up, but I can tell you that you will have more success outside provided you give the seedlings a stable enough environment. Growing Cyps indoors, even as seedlings, is problematic due to insufficient temperature shifts from day to night and dry air conditions. Can it be done? Sure, but it will be challenging.

The best outdoor set-up would be in a shade house with either an eastern or northern exposure with no direct sunlight. On the other hand you want plenty of light, so avoid overhead shading by trees, etc. You can grow them in pots, or in slightly raised beds, but be sure animals, digging rodents, etc. cannot get to them. That will mean both above and below ground barriers. Hardware cloth is a good option for the below ground one.

The species you've chosen are appropriate to your climate. Ron Burch grew kentuckiense successfully in NW Connecticut in pure silica sand beds in such a shade house set-up. This species seems to thrive in silica. Pubescens can be grown in any reasonable compost, but avoid organics (IMO), especially for seedlings. You'll need to fertilize regularly with inorganic composts. Also, never allow the containers/beds to dry out. Humidity should be maintained above 50%.

Good luck!
Thanks for all the help, I ended up modifying the way I originally was going to pot everything up. I actually rec’d my seedlings about 2 1/2 weeks ago, Thank you Spangle Creek! I potted them up and then buried the pots in the ground with about an inch from the soil line then surrounded with hardware to keep the rabbits and deer at bay. I have noticed my Pubescens don’t excellent nd have had huge increases in growth in just the past week. My Kentuckiense has not been experiencing the same growth and I’m starting to believe it’s not enough light. I planted some of the pots along a progressively taller retaining wall that faces north with some hostas. My Cyp Kent. are at a spot where the wall is about 4 ft tall and planted about 1’ from the wall. The Pubescens is planted at a height in the wall at about 5-6’ and also 1’ from the wall. They get full sun in the AM for a few hours but Hostas are starting to shade them out. I’m starting to think this might be a better spot when they are mature.

I have been watering with rain water when I can with a 1/4 diluted 20x20x20 Mericle Grow. I also mixed a small amount of Ozmocote plus slow release into my mix as well.

Anyway since their in pots I guess I will love them around until I find a spot they will be happy. At this time I don’t have the time or resources to build a shade house. Will come with time. I will need to keep everyone updated on their progress. I’ve already posted some updates to Facebook here: (hope this works).
At what point does the cypripedium produce it’s next year rhizome? My 3 year old decided he wanted to become a Gardner too! :noangel: And needless to say he damaged some of my seedlings and they are starting die back. Maybe next year?!

Others are going strong!

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